import com.example.yin.dao.SongMapper;
import com.example.yin.domain.Song;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;

import javax.annotation.Resource;
import java.util.List;

public class testmapper {
    @Autowired
    private SongMapper songMapper;
    @Test
    public void test1(){
        List<Song> songs = songMapper.selectList(null);
        songs.forEach(System.out :: println);
    }

}
